@learncard/sd-jwt-vc-plugin

SD-JWT-VC holder + verifier support for LearnCard. Implements:

• RFC 9901 — Selective Disclosure for JWTs (SD-JWT)
• draft-ietf-oauth-sd-jwt-vc-16 — SD-JWT-VC profile for Verifiable Credentials

Token Status List (revocation / suspension) is on the roadmap — see Slice 4 in the status table below.

Status

Holder read-path: feature-complete. The plugin parses, reconstructs, and verifies SD-JWT-VCs against any DID-resolvable issuer (did:key, did:web, did:jwk). Presentation (KB-JWT signing) lands in Slice 3; status list lands in Slice 4.

| Capability | Status | |---|---| | Parse compact serialization (Issuer JWT + Disclosures + optional KB-JWT) | ✅ Slice 1 | | Reconstruct fully-disclosed claims | ✅ Slice 1 | | Verify issuer signature (via DID resolution) + disclosure hashes | ✅ Slice 1 | | dc+sd-jwt and legacy vc+sd-jwt format strings | ✅ Slice 1 | | Per-claim selective disclosure preview | ✅ Slice 1 | | Wallet display view-model (vct → category) | ⏳ Slice 2 | | Holder presentation + KB-JWT signing | ⏳ Slice 3 | | Token Status List checking (cached + network) | ⏳ Slice 4 |

Spec versions

• SD-JWT: RFC 9901 (Proposed Standard, Nov 2025)
• SD-JWT-VC: draft-ietf-oauth-sd-jwt-vc-16 (May 2026). Format string dc+sd-jwt is canonical; legacy vc+sd-jwt is accepted on read for back-compat.

Architectural notes

• Format-plugin, not transport. The plugin is self-contained — it knows nothing about OID4VCI, OID4VP, or VC-API. The openid4vc plugin delegates to this plugin via learnCard.invoke.parseSdJwtVc(), verifySdJwtVc(), etc.
• Library: @sd-jwt/core + @sd-jwt/sd-jwt-vc (OpenWallet Foundation, Apache-2.0). Callback-based crypto so our existing jose Ed25519 signer plugs in.
• DID resolution: delegated to @learncard/didkit-plugin (resolveDid()). Supports did:key, did:web, did:jwk, did:ethr, did:pkh:*, did:tz.
• Browser-first: no Node-only dependencies. Uses Web Crypto SHA-256, crypto.getRandomValues, and jose.

Installation

pnpm add @learncard/sd-jwt-vc-plugin

Required peer plugin: @learncard/didkit-plugin (for issuer DID resolution).

Usage

import { initLearnCard } from '@learncard/init';

const learnCard = await initLearnCard({ seed: 'a'.repeat(64) });

// Parse only — no network, no verification
const parsed = await learnCard.invoke.parseSdJwtVc(compact);
console.log(parsed.vct);          // 'https://credentials.example.com/...'
console.log(parsed.claims);       // fully-reconstructed payload

// Verify (parses + verifies issuer signature + checks disclosure hashes)
const check = await learnCard.invoke.verifySdJwtVc(compact);
if (check.errors.length > 0) {
    console.error('Verification failed:', check.errors);
}

Errors

All errors thrown by this plugin are SdJwtVcError instances with a stable code field for UI mapping. See src/types.ts for the full code list.

Testing

pnpm --filter @learncard/sd-jwt-vc-plugin test

The unit suite round-trips real credentials end-to-end: each test generates a fresh Ed25519 keypair, issues an SD-JWT-VC via SDJwtVcInstance from the OpenWallet Foundation library, then exercises the plugin's parse / verify paths against the live output. Hand-crafted fixtures cover the negative-shape cases (missing iss, vct, alg).

Cross-implementation conformance against RFC 9901 Appendix A vectors and OpenWallet's published test suite lands as part of Slice 4 (see status table above).

License

MIT © Learning Economy Foundation